REACTIONS OF HUMPBACK WHALES TO SKIN BIOPSY SAMPLING ON A WEST INDIES BREEDING GROUND

Abstract: Reactions of humpback whales, Megaptera novaeangliae , to the taking of skin biopsies and to associated activities were studied on one of their principal West Indies breeding grounds on Silver Bank (Dominican Republic). Results were in some cases different from those reported from a similar study of this species in a high-latitude feeding area. Almost half (44.1%) of 565 biopsied whales showed no immediate reaction to a hit, while a further 22.5% showed only low-level reactions. A total of 375 (87.8%) of 427 misses involved no reaction. Only one strong reaction was recorded. Behavior changes were recorded following 31 (5.5%) of 569 hits, and 18 (4.5%) of 404 misses. Evasive behavior related to vessel approach was exhibited prior to 72 (12.0%) of 598 hits and 100 (24.1%) of 415 misses. Mothers showed significantly fewer reactions to hits than other whales, and a similar frequency and type of behavior changes, although they tended to be more evasive before a shot was made. Presumed males in competitive groups also showed significantly fewer reactions to shots, and very few behavior changes. Overall, this study supports the belief that the biopsy itself has little effect on a whale and that, if the associated vessel approach is conducted with care, samples can usually be taken with minimal disturbance to the target animal. However, approaches may affect the probability of obtaining fluke photographs for individual identification.     

Structure and Dynamics of Minke Whale Surfacing Patterns in the Gulf of St. Lawrence,Canada

Animal behavioral patterns can help us understand physiological and ecological constraints on animals and its influence on fitness. The surfacing patterns of aquatic air-breathing mammals constitute a behavioral pattern that has evolved as a trade-off between the need to replenish oxygen stores at the surface and the need to conduct other activities underwater. This study aims to better understand the surfacing pattern of a marine top predator, the minke whale (Balaenoptera acutorostrata), by investigating how their dive duration and surfacing pattern changes across their activity range. Activities were classified into resting, traveling, surface feeding and foraging at depth. For each activity, we classified dives into short and long dives and then estimated the temporal dependence between dive types. We found that minke whales modified their surfacing pattern in an activity-specific manner, both by changing the expression of their dives (i.e. density distribution) and the temporal dependence (transition probability) between dive types. As the depth of the prey layer increased between activities, the surfacing pattern of foraging whales became increasingly structured, going from a pattern dominated by long dives, when feeding at the surface, to a pattern where isolated long dives were followed by an increasing number of breaths (i.e. short dives), when the whale was foraging at depth. A similar shift in surfacing pattern occurred when prey handling time (inferred from surface corralling maneuvers) increased for surface feeding whales. The surfacing pattern also differed between feeding and non-feeding whales. Resting whales did not structure their surfacing pattern, while traveling whales did, possibly as a way to minimize cost of transport. Our results also suggest that minke whales might balance their oxygen level over multiple, rather than single, dive cycles.     

Activity budget and diving behavior of gray whales (Eschrichtius robustus) in feeding grounds off coastal British Columbia

Behavior and diving patterns of summer resident gray whales ( Eschrichtius robustus ) foraging on mysids were studied in coastal bays along the north shore of Queen Charlotte Strait, British Columbia. In this region, gray whales were found to feed primarily on planktonic prey rather than on the benthos as in their primary feeding areas further north. During the summers of 1999 and 2000, whales spent most of their time actively feeding or searching for prey (77%), whereas only 15% of their time was spent traveling and 8% socializing. The majority of the dives were short; the mean dive duration was 2.24 min with approximately three respirations per surfacing and 15 s between blows. Whales dove frequently (26.7 h⁻¹), spending only 17% of their time at the surface with an overall blow rate of 1.14 respirations per minute. Activity states were characterized by significantly different diving and respiratory parameters; feeding whales dove more frequently, with shorter intervals between respirations, thus spending less time at the surface compared to when traveling or searching. This diving pattern differs from benthic-feeding whales and likely optimizes capture of the mobile mysid swarms in shallow waters.     

FEEDING, SOCIAL AND MIGRATION BEHAVIOR OF BOWHEAD WHALES, BALAENA MYSTICETUS, IN BAFFIN BAY VS. THE BEAUFORT SEA—REGIONS WITH DIFFERENT AMOUNTS OF HUMAN ACTIVITY

This paper compares the behavior of bowhead whales of the Davis Strait/Baffin Bay stock, as observed along the east coast of Baffin Island in 1979–1986, with behavior of the Bering/Chukchi/Beaufort Sea stock observed in the Beaufort Sea in 1980–1986. All data used here were collected during late summer and early autumn in the absence of acute human disturbance. The behavioral repertoires of the two populations were similar. However, quantitative differences were found for whales engaged in all three activities studied: (1) Bowheads feeding in deep water off Isabella Bay, Baffin Island, had longer dives and surfacings, on average, than noted for bowheads feeding in the Beaufort Sea. (2) Among whales socializing in shallow water, we saw sexual interactions more often at Isabella Bay than in the Beaufort Sea. Calls emitted by socializing whales off Baffin Island were similar to those heard in the Chukchi and Beaufort Seas. However, pulsed tonal calls were longer off Baffin Island, and previously undescribed mechanical "crunch" sounds were recorded there near socializing bowheads. (3) During autumn migration, "fluke-out" dives were less common, and dive durations were longer, in the Beaufort Sea than off Baffin Island (P<0.001). Multivariate and other analyses indicated that some but not all differences can be ascribed to regional differences in the natural environment or in whale activities, However, during 1974–1986, Bering/Chukchi/Beaufort bowheads were exposed to more industrial, hunting and other human activity than Davis Strait/Baffin Bay bowheads. The "inconspicuous" behavior during autumn migration in the Beaufort may have been attributable to human activities, but causative links cannot be isolated.     

Migratory movements and surfacing rates of humpback whales (Megaptera novaeangliae) satellite tagged at Socorro Island,Mexico

Humpback whales wintering in the Revillagigedo Archipelago, Mexico, have been considered a different subpopulation from those found off mainland Mexico and Baja California. The primary feeding grounds for Revillagigedo humpbacks remain unknown. In February 2003, we deployed 11 Argos satellite‐monitored radio tags to track movements and surfacings of humpback whales (five adults without calves, five mothers with calves, one calf) off Socorro Island in the Revillagigedo Archipelago. Tracking ranged from 222 to 10,481 km over 4.9–149.1 d. Eight whales left Socorro Island: five visited other Mexican wintering destinations, seven moved north of these areas. Migration routes were primarily offshore (average 444 km). Two whales were tracked to feeding grounds: one to British Columbia (46 d migration), and one to Alaska (49 d migration). Mean travel speeds were 1.2 km/h in wintering areas, 4.0 km/h during migration, and 2.2 km/h in feeding areas. Overall surfacing rates ranged from 21 to 88 surfacings/h. Surfacing rates differed between the calf and all other whales, and between feeding areas and migratory/wintering areas for the calf and an adult without a calf. The calf also showed diel variation in surfacing rates. The offshore habits of tagged whales may explain scarce resightings of Revillagigedo humpbacks outside the Revillagigedo Archipelago.     

Factors driving the variability in diving and movement behavior of migrating humpback whales (Megaptera novaeangliae): Implications for anthropogenic disturbance studies

Humpback whales (Megaptera novaeangliae) undertake one of the longest migrations of any animal and while on a broad‐scale this journey appears direct, on a fine‐scale, behaviors associated with socializing and breeding are regularly observed. However, little is known about which social and environmental factors influence behavior during this time. Here we examined the effect of multiple factors on the movement (speed and course) and diving behavior (dive and surfacing duration) of humpback whales during migration off the eastern coast of Australia. Focal data (202 h) were collected on 94 different whale groups with simultaneous social and environmental context data. The environmental factors water depth and wind speed were found to be important predictors of dive and movement behavior, whereas social factors were less influential at this site. Groups tended to dive for longer with increased water depth but traveled more slowly in increasing wind speeds. These baseline studies are crucial when examining the effect of anthropogenic disturbance. Determining which natural factors significantly affect behavior ensures any observed behavioral changes are correctly attributed to the disturbance and are not a result of other factors. In addition, any responses observed can be put into biological context and their relative magnitude determined.     

INTERCHANGE AND ISOLATION OF HUMPBACK WHALES OFF CALIFORNIA AND OTHER NORTH PACIFIC FEEDING GROUNDS

Humpback whales feed in several high-latitude areas of the North Pacific. We examined the interchange of humpback whales between one of these areas, off California, and those in other feeding grounds in the eastern North Pacific:. Fluke photographs of 597 humpback whales identified off California between 1986 and 1992 were compared with those off Oregon and Washington (29); British Columbia (81); southeastern Alaska (343); Prince William Sound, Alaska (141); Kodiak Island, Alaska (104); Shumagin Islands, Alaska (22); and in the Bering Sea (7). A high degree of interchange, both inter-and intrayear, was found among humpback whales seen off California, Oregon, and Washington., A low rate of interchange was found between British Columbia and California.: two whales seen near the British Columbia/Washington border were photographed off California in a different year, No interchange was found between California and the three feeding areas in Alaska. Humpback whales off California, Oregon, and Washington form a single intermixing feeding aggregation with only limited interchange with areas farther north. These findings are consistent with photographic identification studies in the North Atlantic and with genetic studies in both the North Atlantic and North Pacific.     

GRAY WHALES (ESCHRICHTIUS ROBUSTUS) OFF SAKHALIN ISLAND,RUSSIA: SEASONAL AND ANNUAL PATTERNS OF OCCURRENCE1

The annual return, seasonal occurrence, and site fidelity of Korean-Okhotsk or western gray whales on their feeding grounds off northeastern Sakhalin Island, Russia, were assessed by boat-based photo-identification studies in 1994-1998. A total of 262 pods were observed, ranging in size from 1 to 9 whales with an overall mean of 2.0. Sixty-nine whales were individually identified, and a majority of all whales (71.0%) were observed in multiple years. Annual sighting frequencies ranged from 1 to 18 d, with a mean of 5. 4 d. The percentage of whales reidentified from previous years showed a continuous annual increase, reaching 87.0% by the end of the study. Time between first and last sighting of identified individuals within a given year was 1-85 d, with an overall mean of 40.6 d. Annual calf proportions ranged from 4.3% (1997) to 13.2% (1998), and mother-calf separations generally occurred between July and September. The seasonal site fidelity and annual return of whales to this part of the Okhotsk Sea emphasize its importance as a primary feeding ground for this endangered population.     

The diving behavior of blue and fin whales: is dive duration shorter than expected based on oxygen stores?

Many diving seabirds and marine mammals have been found to regularly exceed their theoretical aerobic dive limit (TADL). No animals have been found to dive for durations that are consistently shorter than their TADL. We attached time-depth recorders to 7 blue whales and 15 fin whales (family Balaenopteridae). The diving behavior of both species was similar, and we distinguished between foraging and traveling dives. Foraging dives in both species were deeper, longer in duration and distinguished by a series of vertical excursions where lunge feeding presumably occurred. Foraging blue whales lunged 2.4 (+/-1.13) times per dive, with a maximum of six times and average vertical excursion of 30.2 (+/-10.04) m. Foraging fin whales lunged 1.7 (+/-0.88) times per dive, with a maximum of eight times and average vertical excursion of 21.2 (+/-4.35) m. The maximum rate of ascent of lunges was higher than the maximum rate of descent in both species, indicating that feeding lunges occurred on ascent. Foraging dives were deeper and longer than non-feeding dives in both species. On average, blue whales dived to 140.0 (+/-46.01) m and 7.8 (+/-1.89) min when foraging, and 67.6 (+/-51.46) m and 4.9 (+/-2.53) min when not foraging. Fin whales dived to 97.9 (+/-32.59) m and 6.3 (+/-1.53) min when foraging and to 59.3 (+/-29.67) m and 4.2 (+/-1.67) min when not foraging. The longest dives recorded for both species, 14.7 min for blue whales and 16.9 min for fin whales, were considerably shorter than the TADL of 31.2 and 28.6 min, respectively. An allometric comparison of seven families diving to an average depth of 80-150 m showed a significant relationship between body mass and dive duration once Balaenopteridae whales, with a mean dive duration of 6.8 min, were excluded from the analysis. Thus, the short dive durations of blue whales and fin whales cannot be explained by the shallow distribution of their prey. We propose instead that short duration diving in large whales results from either: (1) dispersal behavior of prey; or (2) a high energetic cost of foraging.     

KILLER WHALE PREDATION ON SPERM WHALES: OBSERVATIONS AND IMPLICATIONS

In October 1997 we observed a herd of approximately 35 killer whales ( Orcinus orca ) attack a pod of nine sperm whales ( Physeter macrocephalus ) 130 km off the coast of central California. During the four hours we watched, adult female killer whales, including some with calves, attacked in waves of four to five animals in what was apparently a "wound and withdraw" strategy. Adult male killer whales stood by until the very end when one charged in and quickly killed a seriously wounded sperm whale that had been separated from the group. The sperm whales appeared largely helpless: their main defensive behavior was the formation of a rosette ("marguerite"-heads together, tails out). When the killer whales were successful in pulling an individual out of the rosette, one or two sperm whales exposed themselves to increased attack by leaving the rosette, flanking the isolated individual, and leading it back into the formation. Despite these efforts, one sperm whale was killed and eaten and the rest were seriously, perhaps mortally, wounded. We also present details of two other encounters between sperm whales and killer whales that we observed. Although sperm whales, because of various behavioral and morphological adaptations, were previously thought to be immune to predation, our observations clearly establish their vulnerability to killer whales. We suggest that killer whale predation has potentially been an important, and underrated, selective factor in the evolution of sperm whale ecology, influencing perhaps the development of their complex social behavior and at-sea distribution patterns.     

Dangerous dining: surface foraging of North Atlantic right whales increases risk of vessel collisions

North Atlantic right whales are critically endangered and, despite international protection from whaling, significant numbers die from collisions with ships. Large groups of right whales migrate to the coastal waters of New England during the late winter and early spring to feed in an area with large numbers of vessels. North Atlantic right whales have the largest per capita record of vessel strikes of any large whale population in the world. Right whale feeding behaviour in Cape Cod Bay (CCB) probably contributes to risk of collisions with ships. In this study, feeding right whales tagged with archival suction cup tags spent the majority of their time just below the water's surface where they cannot be seen but are shallow enough to be vulnerable to ship strike. Habitat surveys show that large patches of right whale prey are common in the upper 5 m of the water column in CCB during spring. These results indicate that the typical spring-time foraging ecology of right whales may contribute to their high level of mortality from vessel collisions. The results of this study suggest that remote acoustic detection of prey aggregations may be a useful supplement to the management and conservation of right whales.     

A CETACEAN BIOPSY SYSTEM USING LIGHTWEIGHT PNEUMATIC DARTS, AND ITS EFFECT ON THE BEHAVIOR OF KILLER WHALES

Lightweight untethered pneumatic darts were used to biopsy killer whales, Orcinus orca , for genetic and toxicological analysis. Samples of epidermal, dermal, and hypodermal tissue weighing approximately 0.5 g were obtained by 65% of the 91 darts fired during the study. Sufficient DNA for multiple analyses was extracted from the biopsies, which were also used for fatty acid and toxic contaminant analyses. Reactions such as momentary shakes or accelerations were observed after 81% of the dart hits and 53% of the misses. Aversion to the research vessel was assessed by reapproaching target whales after the sampling attempts. In 6% of the hits and 8% of the misses aversion to the research boat increased immediately following the attempt. No similar increases in aversion were seen when killer whales were reapproached one day to one year after being hit. The darts were also tested successfully on humpback whales, Megaptera novaeangliae . In view of the simplicity of the system, its effectiveness in acquiring multipurpose samples, and the apparently short-term disturbance it caused, it is recommended for future cetacean biopsy studies.     

Interactions between killer whales (<Emphasis Type="Italic">Orcinus orca</Emphasis>) and Steller sea lions (<Emphasis Type="Italic">Eumetopias jubatus</Emphasis>) in the vicinity of Brat Chirpoev Island,Kuril Islands

The behaviors of breeding Steller sea lions in response to encounters with killer whales near the shore were observed on Brat Chirpoev Island, Kuril Islands between May and July 2002–2007. Approaches by killer whales and sea lion behavior was observed visually and recorded. Killer whales approached the rookery 104 times during the entire period of observations (289 days). In most cases (n = 95), beached sea lions did not show any apparent reactions to the presence of killer whales, and there were no observed interactions. Sea lions showed agitation during nine of the approaches; five of these events were considered to be predation attempts. The killer whales attacked the sea lions three times, however all the attacks were unsuccessful. We recorded two different types of responses towards the killer whales: (1) beaching on the shore (three times) and (2) mass exodus from the rookery with subsequent formation of a tight, actively swimming and vocalizing group (six times). The latter is the first recorded observation of this behavior for Steller sea lions. The observation suggests a low degree of interactions between these two species near the studied rookery. Despite the numerous observations of killer whales near the rookery, there were no observations of direct predation on sea lions. It is likely the killer whale predation has little or no direct impact on the Steller sea lion population on Brat Chirpoev Islands during the breeding period.     

CATCHES OF HUMPBACK AND OTHER WHALES FROM SHORE STATIONS AT MOSS LANDING AND TRINIDAD, CALIFORNIA, 1919–1926

Logbook data from California shore whaling stations at Moss Landing (1919–1922 and 1924) and Trinidad (1920 and 1922–1926) are analyzed. The logs for the two stations record the taking of 2,111 whales, including 1,871 humpbacks, 177 fin whales, 26 sei whales, 3 blue whales, 12 sperm whales, 7 gray whales, 1 right whale, 1 Baird's beaked whale, and 13 whales of unspecified type (probably humpbacks). Most whales were taken from spring to autumn, but catches were made in all months of some years. The sex ratios of humpback, fin, and sei whales (the three species with sufficient sample sizes to test) did not differ from parity. Primary prey, determined from stomach contents, included sardines and euphausiids for both humpback and fin whales, and 'plankton' (probably euphausiids) for sei whales. The prevalence of pregnancy was 0.46 among mature female humpbacks and 0.43 among mature female fin whales, although these values are reported with caution. Information on length distribution for all species is summarized. Analysis of the catch data for this and other areas supports the current view that humpback whales along the west coast of the continental United States comprise a single feeding stock and also suggests that the present population is well below pre-exploitation levels.     

GRAY WHALE (ESCHRICHTIUS ROBUSTUS) HABITAT UTILIZATION AND PREY SPECIES OFF VANCOUVER ISLAND, B. C.

Habitat utilization and prey species of Vancouver Island gray whales were investigated by (1) summarizing 26 yr of distribution and feeding data and (2) conducting intensive observations in Clayoquot Sound, Vancouver Island, from 1989 to 1996. Whale distribution and movements were monitored from March to November through systematic boat surveys and whale-watch sighting programs. Prey species were collected by suction hose and plankton net or determined through analysis of fecal samples. Gray whales utilized virtually all of the southern west coast of Vancouver Island over the 26-yr observation period. Distribution, prey species, and feeding behavior showed marked variability during any one season and between years. Some feeding areas were used on an annual basis, others with >10-yr intervals between use. Feeding occurred in shallow sand or mud bays, eel grass beds, kelp beds, in the open water column, and at the surface. Young whales appeared to utilize habitat and prey species differently than adults. Main prey species included herring eggs/larvae ( Clupea harengus pallasi ), crab larvae ( Cancer magister megalops, Pachycbeles spp. zoea), mysids ( Holmesimysis sculpta, Neomysis rayii, Acanthomysis spp.), amphipods ( Ampelisca spp., Atylus borealis ), and ghost shrimp ( Callianassa californiensis ). The definition and relative importance of specific feeding grounds and the study of human impacts on this population are complicated by its broad and variable use of habitat and prey species.     

Humpback whale (Megaptera novaeangliae) and killer whale (Orcinus orca) feeding aggregations for foraging on herring (Clupea harengus) in Northern Norway

Aggregations of predators on food patches have been documented for both terrestrial and marine animals. Here, we documented for the first time, and investigated, non-predatory aggregations occurring between humpback whales (Megaptera novaeangliae) and killer whales (Orcinus orca) while feeding on wintering Norwegian spring spawning herring (Clupea harengus) in Andfjord, northern Norway. Observational data were collected during 109 opportunistic surveys through three seasons 2013–2016. Killer whales were observed feeding on 59 occasions, with one to three humpback whales involved in 47 of these feeding events (79.7%), and there was an increased probability of finding feeding humpback whales when feeding killer whales also were observed. With killer whales identified as the initiating species in 94.4% of the feeding aggregations for which the first species was known, and with humpback whales joining and feeding on the fish ball afterwards, we suggest that humpback whales may benefit more from these aggregations than the opposite.     

HISTORICAL OBSERVATIONS OF HUMPBACK AND BLUE WHALES IN THE NORTH ATLANTIC OCEAN: CLUES TO MIGRATORY ROUTES AND POSSIBLY ADDITIONAL FEEDING GROUNDS

The seasonal distributions of humpback and blue whales ( Megaptera novaeangliae and Balaenoptera musculus , respectively) in the North Atlantic Ocean are not fully understood. Although humpbacks have been studied intensively in nearshore or coastal feeding and breeding areas, their migratory movements between these areas have been largely inferred. Blue whales have only been studied intensively along the north shore of the Gulf of St. Lawrence, and their seasonal occurrence and movements elsewhere in the North Atlantic are poorly known. We investigated the historical seasonal distributions of these two species using sighting and catch data extracted from American 18th and 19th century whaling logbooks. These data suggest that humpback whales migrated seasonally from low-latitude calving/ breeding grounds over a protracted period, and that some of them traveled far offshore rather than following coastal routes. Also, at least some humpbacks apparently fed early in the summer west of the Mid-Atlantic Ridge, well south of their known present-day feeding grounds. In assessing the present status of the North Atlantic humpback population, it will be important to determine whether such offshore feeding does in fact occur. Blue whales were present across the southern half of the North Atlantic during the autumn and winter months, and farther north in spring and summer, but we had too few data points to support inferences about these whales' migratory timing and routes.     

Stable carbon and nitrogen isotope ratios in muscle and epidermis of arctic whales

Collection of minimally invasive biopsy samples has become an important method to establish normal stable isotopes reference ranges in various wildlife species. Baseline data enhance the understanding of feeding ecology, habitat use, and potential food limitation in apparently healthy, free‐ranging cetaceans. Epidermis and muscle were collected from subsistence‐hunted northern Alaskan bowhead (n= 133 epidermis/134 muscle) and beluga whales (n= 42/49) and subsistence‐hunted Russian gray whales (n= 25/17). Additional samples were obtained from gray whales stranded in California (n= 18/11) during mortality events (1999, 2000). Both δ¹⁵N and δ¹³C are trophic position and benthic/pelagic feeding indicators, respectively, in muscle and epidermis. Epidermis is generally enriched in ¹⁵N over muscle, while epidermal ¹³C is more depleted. Lipid extraction does not alter δ¹⁵N in either tissue, but affects epidermal δ¹³C. Nitrogen‐15 is enriched in muscle, but not epidermis of stranded compared to subsistence‐hunted gray whales, indicating probable protein catabolism and nutritional stress in stranded whales. Similarly, epidermal δ¹³C of harvested whales is lower than in stranded whales, suggesting depleted lipid stores and/or food limitation in stranded animals. Epidermal isotope signatures are similar in both present‐day bowheads and in an ancient sample from the Northern Bering Sea region. Although only one specimen, this suggests trophic level of the ancient whale compares to modern bowheads after a millennium.     

MOVEMENTS OF NORTH PACIFIC BLUE WHALES DURING THE FEEDING SEASON OFF SOUTHERN CALIFORNIA AND THEIR SOUTHERN FALL MIGRATION1

The satellite-acquired locations of 10 blue whales (Balaenoptera musculus) tagged off southern California with Argos radio tags were used to identify (1) their movements during the late summer feeding season; (2) the routes and rate of travel for individuals on their southern fall migration; and (3) a possible winter calving/breeding area. Whales were tracked from 5.1 to 78.1 d and from 393 to 8,668 km. While in the Southern California Bight, most of the locations for individual whales were either clumped or zigzagged in pattern, suggesting feeding or foraging (searching for prey). Average speeds ranged from 2.4 to 7.2 km/h. One whale moved north to Cape Mendocino, and four migrated south along the Baja California, Mexico coast, two passing south of Cabo San Lucas on the same day. One of the latter whales traveled an additional 2,959 km south in 30.5 d to within 450 km of the Costa Rican Dome (CRD), an upwelling feature. The timing of this migration suggests the CRD may be a calving/breeding area for North Pacific blue whales. Although blue whales have previously been sighted in the Eastern Tropical Pacific (ETP), this is the first evidence that whales from the feeding aggregation off California range that far south. The productivity of the CRD may allow blue whales to feed during their winter calving/breeding season, unlike gray whales (Eschrichtius robustus) and humpbacks (Megaptera novaeangliae) which fast during that period.     

Whales from space: Four mysticete species described using new VHR satellite imagery

Large‐bodied animals such as baleen whales can now be detected with very high resolution (VHR) satellite imagery, allowing for scientific studies of whales in remote and inaccessible areas where traditional survey methods are limited or impractical. Here we present the first study of baleen whales using the WorldView‐3 satellite, which has a maximum spatial resolution of 31 cm in the panchromatic band, the highest currently available to nonmilitary professionals. We manually detected, described, and counted four different mysticete species: fin whales (Balaenoptera physalus) in the Ligurian Sea, humpback whales (Megaptera novaeangliae) off Hawaii, southern right whales (Eubalaena australis) off Península Valdés, and gray whales (Eschrichtius robustus) in Laguna San Ignacio. Visual and spectral analyses were conducted for each species, their surrounding waters, and nonwhale objects (e.g., boats). We found that behavioral and morphological differences made some species more distinguishable than others. Fin and gray whales were the easiest to discern due to their contrasting body coloration with surrounding water, and their prone body position, which is proximal to the sea surface (i.e., body parallel to the sea surface). These results demonstrate the feasibility of using VHR satellite technology for monitoring the great whales.